Targeting the nucleotide salvage factor DNPH1 sensitizes
<i>BRCA</i>
-deficient cells to PARP inhibitors
作者:Kasper Fugger、Ilirjana Bajrami、Mariana Silva Dos Santos、Sarah Jane Young、Simone Kunzelmann、Geoff Kelly、Graeme Hewitt、Harshil Patel、Robert Goldstone、Thomas Carell、Simon J. Boulton、James MacRae、Ian A. Taylor、Stephen C. West
DOI:10.1126/science.abb4542
日期:2021.4.9
poly(ADP-ribose) polymerase (PARP). We show that inhibition of DNPH1, a protein that eliminates cytotoxic nucleotide 5-hydroxymethyl-deoxyuridine (hmdU) monophosphate, potentiates the sensitivity of BRCA-deficient cells to PARP inhibitors (PARPi). Synthetic lethality was mediated by the action of SMUG1 glycosylase on genomic hmdU, leading to PARP trapping, replication fork collapse, DNA break formation
BRCA1或BRCA2肿瘤抑制基因的突变使个体易患乳腺癌和卵巢癌。在临床上,这些癌症采用针对聚(ADP-核糖)聚合酶(PARP)的抑制剂进行治疗。我们发现,抑制 DNPH1(一种消除细胞毒性核苷酸 5-羟甲基脱氧尿苷 (hmdU) 单磷酸盐的蛋白质)可增强BRCA缺陷细胞对 PARP 抑制剂 (PARPi) 的敏感性。合成致死性是由 SMUG1 糖基化酶对基因组 hmdU 的作用介导的,导致 PARP 捕获、复制叉塌陷、DNA 断裂形成和细胞凋亡。获得 PARPi 抗性的BRCA1缺陷细胞通过 hmdU 和 DNPH1 抑制处理重新敏感。由于基因组 hmdU 是 PARPi 敏感性的关键决定因素,因此靶向 DNPH1 为BRCA缺陷型癌症对 PARPi 治疗的超敏化提供了一种有前景的策略。